JBC：三种蛋白在神经细胞修复过程中起着重要作用

生物谷报道：俄亥俄州哥伦布市--一项新的研究表明成熟脑细胞表面的三种特定蛋白量的增加可促使细胞产生新的生长延伸.该研究探讨了小鼠脑神经细胞上的三个相关的受体蛋白:GPR3, GPR6和GPR12.当研究人员增加这三种蛋白的量后,细胞生长延伸比蛋白水平正常时的神经细胞的生长延伸长三倍、延伸速度比对照细胞快4-8倍. "俄亥俄州立大学医学中心的项目主持人Yoshinaga Saeki说."我们的研究结果显示,这三种蛋白可能是用于治疗中风,脑和脊髓损伤及神经退行性疾病的重要靶点“该研究刊登在4月6日的《生物化学》杂志上.
这些蛋白量的增加与神经细胞cAMP内的一种重要的信号分子的水平的增加有关.这个分子在调控神经细胞生长、分化和生存, 及传输神经冲动的轴突的再生中起着关键作用.随着哺乳动物神经细胞的成熟,其细胞内的cAMP水平下降,这是解释为什么成熟神经细胞受损的轴突不能再生的部分原因.神经外科副教授,俄亥俄州州立dardinger神经肿瘤及神经科学实验室主管Saeki声称."我们的发现为cAMP在轴突生长中起着重要作用这一观点提供了更多证据,并显示这些受体蛋白可能在调节神经细胞cAMP的产生中起主要作用.”
该研究的第一作者Shigeru Tanaka是Saeki所在实验室的一名博士后研究员. 在本项研究中,他与同事从小鼠与大鼠脑组织神经母细胞瘤中取得神经细胞,使之在培养基中生长以了解更多关于这三种蛋白及其调控cAMP生长中的作用.他们向这些细胞中注入三种基因以增加这三种蛋白的含量水平, 然后用一种被称为核糖核酸干扰的实验室技术关闭这三种蛋白的产生.上述三个蛋白分子中GPR3在神经细胞中最为丰富,而GPR12刺激神经细胞延伸的作用最强. 研究表明阻断GPR3的产生就大大减慢了神经细胞的生长速度,研究者们通过修复GPR3或GPR12的产生扭转了这种效应.三种蛋白质的含量水平高也与较高水平的cAMP有关, 同时GPR6和GPR12能增加两倍到三倍的水平.
"总的来说,"Saeki说, "我们的研究结果显示,这三种蛋白能加快神经细胞的生长即使在抑制分子的存在下也是如此,我们迫切希望能找出可以在临床前中风或脊髓损伤动物模型身上重现此结果的方法. "

原文出处：

Shigeru Tanaka, Ken Ishii, Kazue Kasai, Sung Ok Yoon, and Yoshinaga Saeki

Neural Expression of G Protein-coupled Receptors GPR3, GPR6, and GPR12 Up-regulates Cyclic AMP Levels and Promotes Neurite Outgrowth
J. Biol. Chem. 2007 282: 10506-10515. First Published on February 6, 2007; doi:10.1074/jbc.M700911200 [Abstract] [Full Text] [PDF] [Supplemental Data]

相关基因：

GPR3

Official Symbol: GPR3 and Name: G protein-coupled receptor 3 [Homo sapiens]

Other Aliases: ACCA

Other Designations: OTTHUMP00000043209; adenylate cyclase constitutive activator

Chromosome: 1; Location: 1p36.1-p35

MIM: 600241

GeneID: 2827

GPR6

Official Symbol: GPR6 and Name: G protein-coupled receptor 6 [Homo sapiens]

Chromosome: 6; Location: 6q21

MIM: 600553

GeneID: 2830

GPR12

Official Symbol: GPR12 and Name: G protein-coupled receptor 12 [Homo sapiens]

Other Aliases: GPCR12, GPCR21, MGC138349, MGC138351

Chromosome: 13; Location: 13q12

MIM: 600752

GeneID: 2835

作者简介：

Yoshinaga Saeki, M.D., Ph.D.

Research Area:

• Gene- and cell-based therapy for neurological disorders
• Development and applications of viral vectors

Current Research:

My laboratory is developing therapeutic strategies for neurological disorders. We are engaged in three major ongoing projects that employ multidisciplinary research techniques.

1. Developing and applying herpes simplex virus (HSV)-based amplicon vectors for gene therapy and neuroscience research; HSV amplicon vectors are plasmid-based, high-capacity vectors that have full HSV infection machinery.
• identifying and characterizing cellular and immunological mechanisms that regulate HSV amplicon-mediated transgene expression
• developing “indicator” HSV amplicon vectors to monitor various cellular activities
• genetic engineering of neuronal cells using “regulatable” HSV amplicon vectors
2. Development and applications of engineered, oncolytic HSV vectors for brain tumor therapy.
• identifying and characterizing cellular and immunological mechanisms that interfere with oncolytic activities of replication-conditional HSV vectors
• developing novel oncolytic virotherapies that target brain tumor stem cells
3. Studying the roles of three related orphan G protein-coupled receptors, GPR3, GPR6, and GPR12, in the mammalian central nervous system
• defining the functions of GPR3, GPR6, and GPR12 using knockout mice and cultured primary neurons
• defining the roles of GPR3, GPR6, and GPR12 in neurological disorders, such as spinal cord injury and stroke

Techniques:

• Molecular biology: cloning of genes; construction of viral vectors; cloning and engineering viral genomes; BAC engineering; ChIP-PCR; pulsed field-gel electrophoresis (PFGE); GFP and epitope tagging; and purification of His-tagged proteins.
• Cell Biology: transfection of cultured cells; RNAi; immunocytochemistry; FACS analysis; immunoblotting; immunoprecipitation; and primary neural cultures.
• Imaging: confocal microscopic imaging; time-lapse fluorescent microscopic imaging; and in vivo bioluminescence imaging.
• Transgenic mice and small animal surgery: in vivo gene transfer.